Squares as pointers that direct our attention at not only how the light is coming in from the window and interacting with the space of this room, but also to the presence of the white wall itself as a blank canvas, but with qualities of its own.
The six squares mirror the windows on the other side of the room in term of their position and size, pointing to this relationship between light and space, as well as pointing to the comparison and assimilation of the whiteness of the wall and the color of the sky.